Polypropylene Modified with Polyethylene Through Reactive Melt Blending: Fabrication and Characterizations
Changgyu Lim1, Yujin Jang1,2, Young-Wook Chang1,2
1Department of Chemical Engineering, Hanyang University, Ansan 15588, Republic of Korea.
Polymers
|January 11, 2025
Summary
Modifying polypropylene (PP) with polyethylene (PE) created a crosslinked polymer network, significantly improving its melt properties. This enhanced PP is now suitable for producing microcellular foams with a closed-cell structure.
Area of Science:
- Polymer Science
- Materials Science
- Rheology
Background:
- Conventional linear polypropylene (PP) exhibits poor rheological properties, hindering its suitability for foam processing.
- Enhancing PP's melt characteristics is crucial for developing advanced foamed materials.
Purpose of the Study:
- To modify polypropylene (PP) by reactive melt blending with polyethylene (PE) to improve its rheological properties for foam processing.
- To investigate the formation of a crosslinked polymer network and its impact on PP's melt behavior and foamability.
Main Methods:
- Reactive melt blending of maleic anhydride-grafted PP (MA-PP) with glycidyl-bearing PE (G-PE).
- Characterization using FTIR spectroscopy, solubility tests, and rheological measurements.
- Foaming tests utilizing supercritical carbon dioxide (scCO2) in an autoclave.
Main Results:
- An anhydride-epoxy reaction formed a crosslinked polymer network in the modified PP.
- The modified PP displayed enhanced melt elasticity and a pronounced shear-thinning effect compared to pristine PP.
- Successful production of microcellular closed-cell foams from the modified PP, unachievable with neat PP.
Conclusions:
- Reactive blending of MA-PP and G-PE effectively enhances PP's rheological properties for foam applications.
- The crosslinked network structure is key to achieving improved melt behavior and microcellular foam formation.
- This modified PP offers a viable pathway for producing high-performance microcellular foams.
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